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About PUD

Joust pointed out the bootstrap circuit on these older amps.
The C1 Cap 250 v 10 uf was bad bad bad.
it leaked a Loooong time ago and then just dried out.
when testing it looked ok.
BUT when voltage is applied the breakdown will then show up.
The 10vdc zener had to show a drop of 10vdc from the rail voltage when testing from 87 vdc to 77 vdc.
there was no drop at all.
Bad Cap!
What made me finally think of what was going on I looked at the schematic for the bootstrap and the service bulletins point at the High voltage
being present on the board.
C1 Cap
I had 2 of these amps with the same thing that I got from a sound man at the same time
for real cheap..........
Replaced the other one with the same exact problem C1 cap and now have 2 amps that work just fine.
That was the problem!
Testing caps "in circuit" is tough to read and pulling every cap is not very practical.
Thanks again Joust
PUD

Thanks J
This ones been kicking my *beep* for a while,
I dont have a lot of time these days but usually I nail these right away.
Will ck the ballast this AM
Will post right away
PUD
Rev:
Just tested the zener has 85v on both sides measuring from ground to the diode
You should have 10 volts on the Zener diode D8 and it should be 10V higher than the positive rail voltage
10 volts higher that the rail??
confused on that.
PUD

I have been reading up in this site for every bit of info on the CE1000 amps.
I have pulled and replaced suspect Caps and tested all the semiconductors.
Amp will cycle on with no spkr hook up
8 ohms spkr and it will go into fault
I am getting the 15 +/-
And the 24 vdc
BUT
only 74 VDC +/- at all test points indicated on the main PC board
The Schematic says 87 VDC+/-
The Bootstrap and the Thermo protect
One thing here About the pwr transformer I read this!!!
The device in the transformer is a 100 degree C thermal switch and is one three heat sensors built into the amp that can trigger the fault circuit.
The CE2000 transformer is a proprietary transformer and design information is confidential. However I can say that there is three power supplies the Low Voltage +/- 15v Supply, the Bootstrap supply and the High voltage Vcc+/Vcc- (+/-85v for the CE1000 and +/-98v for the CE2000.
This is a simple transformer thats built for Crown, this should not be a secret, the power supply is key to any repair
Is there anyone here that has an Idea about the 74vdc! thats low for this schematic.
And any schematic for the transformer!!?????
Thanks
PUD

Caps is the first thing I would go for, even freeze the transistors/ic circuits. Hot-cold with the iron sometimes will make the part fail...... I have even had noisy resistors.
Sometimes tapping on the components.
These kind of glitches can be a real bear other that swapping out each board/ parts
PUD

Binderyequip@gmail.com
CH 1 8 ohms on 1 output, signal is on the green led and increase of input will get the red clip led to start to cone on.
Ch 2 is the same
Test 1 channel at a time
Both Ch's are out
Cked all the SMT emitter resistors
Cked all driver leads
If any output transistor was bad you should get a fault
Inspected the main board and wiring very close along with testing every diode,trans,cap,
Heat sinks cold.
theres a mute circuit but to hear the relays kick in after you get the 6 seconds from "turned on"
Just for fun I will open J2 lead 3 to see if the fault will trigger and fan come on
I must be missing something real simple here guys
PUD

Is there a diagram on the transformer therm protect , my question is the J2 pins 3&4 on the 15VDC to the transformer getting 2.1vdc pin 3 &4 to gnd
I posted info on what I have tested so far using the diagrams from the web site for this CE1000.
BTW no faults on led's except on Ch 2 clipping sometimes
any help ?
thanks guys
Pud